<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
      class="page-nav-bar"
      left-arrow
      title="黑马头条"
      @click-left="$router.back()"
    ></van-nav-bar>

    <div class="main-wrap">
      <!-- 加载中 -->
      <div class="loading-wrap" v-if="loading">
        <van-loading color="#3296fa" vertical>加载中</van-loading>
      </div>
      <!-- /加载中 -->

      <template v-else>
        <!-- 加载完成-文章详情 -->
        <div class="article-detail" v-if="errorCode===1">
          <!-- 文章标题 -->
          <h1 class="article-title">{{article.title}}</h1>
          <!-- /文章标题 -->

          <!-- 用户信息 -->
          <van-cell class="user-info" center :border="false">
            <van-image
              class="avatar"
              slot="icon"
              round
              fit="cover"
              :src="article.aut_photo"
            />
            <div slot="title" class="user-name">{{article.aut_name}}</div>
            <div slot="label" class="publish-date">{{article.pubdate | relativeTime }}</div>
            <!-- 关注组件 -->
            <!-- 
              组件上面的class会被移入到组件模板的根标签上面 

              :is-followed="article.is_followed"
              @update-followed="article.is_followed=$event" 
              
              <组件 v-model="变量" />
              <组件 :value="变量" @input="变量=$event" />
              组件内部 定义了value的prop属性，和$emit触发了input自定义事件
              一个组件上面只能有一个v-model指令
            -->
            <follow-user 
              class="follow-btn" 
              :user-id="article.aut_id"
              v-model="article.is_followed"
            />
          </van-cell>
          <!-- /用户信息 -->

          <!-- 文章内容 -->
          <div class="article-content markdown-body" ref="content" v-html="article.content"></div>
          <van-divider>正文结束</van-divider>

          <!-- 评论列表 -->
          <comment-list 
            :source-id="article.art_id" 
            @set-comment-total="commentTotal=$event" 
            :list="commentList"
            @click-reply="onClickReply"
          />
          <!-- /评论列表 -->
          <!-- 文章评论弹框 -->
          <van-popup 
            v-model="isPostShow" 
            position="bottom"
          >
            <comment-post
              :target="article.art_id"
              :list="commentList"
              @close="isPostShow=false"
              @update-comment-total="commentTotal++"
            />
          </van-popup>
          <!-- /文章评论弹框 -->

          <!-- 评论回复弹框 -->
          <van-popup 
              v-model="isReplyShow" 
              position="bottom"
              :style="{height:'100%'}"
            >
            <comment-reply
              v-if="isReplyShow"
              :comment="currentComment"
              :article-id="article.art_id"
              @click-close="isReplyShow=false"
            />
          </van-popup>
          <!-- /评论回复弹框 -->

          <!-- 底部区域 -->
          <div class="article-bottom">
            <van-button  @click="isPostShow=true" class="comment-btn" type="default" round size="small"
              >写评论</van-button
            >

           

            <van-icon name="comment-o" :badge="commentTotal" color="#777" />
            <!-- 收藏组件 -->
            <!-- 
              <article-collect
                :value="article.is_collected"
                @input="article.is_collected=$event"
              />
             -->
            <article-collect 
              :article-id="article.art_id" 
              v-model="article.is_collected" 
            />

            <!-- 点赞 -->
            <!-- 
              :article-attitude="article.attitude"
              @update:article-attitude="article.attitude=$event"
             -->
            <article-like
              :article-attitude.sync="article.attitude"
              :article-id="article.art_id" 
            />

            <van-icon name="share" color="#777777"></van-icon>
          </div>
          <!-- /底部区域 -->
        </div>
        <!-- /加载完成-文章详情 -->

        <!-- 加载失败：404 -->
        <div class="error-wrap"  v-if="errorCode===2">
          <van-icon name="failure" />
          <p class="text">该资源不存在或已删除！</p>
        </div>
        <!-- /加载失败：404 -->

        <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
        <div class="error-wrap"  v-if="errorCode===3">
          <van-icon name="failure" />
          <p class="text">内容加载失败！</p>
          <van-button class="retry-btn" @click="loadArticle">点击重试</van-button>
        </div>
        <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
      </template>
    </div>
  </div>
</template>

<script>
import { getArticleById } from "@/api/article";
import { ImagePreview } from 'vant'
import FollowUser from '@/components/follow-user'
import ArticleCollect from '@/components/article-collect'
import ArticleLike from '@/components/article-like'
import CommentList from './components/comment-list'
import CommentPost from './components/comment-post';
import CommentReply from './components/comment-reply';
export default {
  name: "ArticleIndex",
  components:{
    FollowUser,ArticleCollect,ArticleLike,CommentList,
    CommentPost,
    CommentReply
  },
  data() {
     return {
      // 文章数据
      article: {},
      loading: false, // 加载中变量
      errorCode:1,  // 1没有错误 2是404  3是不正常
      commentTotal:'',  // 评论总数量
      isPostShow:false, // 文章评论回复弹框
      commentList:[],   // 评论或回复列表
      isReplyShow:false, // 评论回复弹框
      currentComment:{}   // 当前点击项
    }; 
  },
  props: {
    articleId: {
      type: [String, Number,Object],
      required: true
    }
  },
  created() {
  // activated() {
    console.log("文章详情被创建了");
    this.loadArticle();
    // 此时模板还没有编译！
  },
  // mounted(){
  //   console.log("父亲挂载了");
  //   this.loadArticle();     // 写在这里有问题，因为模板已经编译了一次！ 
  //   第一次模板用的是默认数据，导致传入到组件里面的props都没有数据
  // },
  methods: {
    // 加载文章数据
    async loadArticle() {
      this.loading = true; // 加载中
      try {
        // 发送请求，赋值操作
        // let { data:res } = await getArticleById(this.$route.params.id)
        let { data: res } = await getArticleById(this.articleId);
        this.article = res.data;
        this.loading = false; // 关闭加载中  
        this.errorCode = 1
        // 等到DOM渲染完成  
        this.$nextTick(()=>{
            this.showImg()
        })

      } catch (error) {
         this.loading = false; // 关闭加载中
        if(error.response.status === 404){
          this.errorCode = 2
        }else{
          this.errorCode = 3
        }
      }
    },
    showImg(){
     // 获取到所有img集合
      let imglist = this.$refs.content.querySelectorAll('img')
      let imgsrc_arr = []  // 图片地址数组
      imglist.forEach(img=>{
        // 取出地址
        imgsrc_arr.push(img.src)
      })
      imglist = Array.from(imglist)
      // 循环绑定事件，调用预览
      for(let i=0; i<imglist.length; i++){
        imglist[i].onclick = function(){
          ImagePreview({
            images:imgsrc_arr,
            startPosition:i
          })
        }
      }
    },
    onClickReply(val){
      // 接收 comment-item==>comment-list===>index 的点击行数据
      this.currentComment = val
      this.isReplyShow = true
    }
  }
  
};
</script>

<style lang="less" scoped>
@import url(./github-markdown.css);
.article-container {
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    z-index: 100;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>
